DOM and DOMSource Examples (The Java EE 5 Tutorial)

The Java EE 5 Tutorial

DOM and DOMSource Examples

The examples DOMExample.java and DOMSrcExample.java show how to add a DOM document to a message and then traverse its contents. They show two ways to do this:

DOMExample.java creates a DOM document and adds it to the body of a message.
DOMSrcExample.java creates the document, uses it to create a DOMSource object, and then sets the DOMSource object as the content of the message’s SOAP part.

You will find the code for DOMExample and DOMSrcExample in the following directory:

tut-install/javaeetutorial5/examples/saaj/dom/src/

Examining the `DOMExample` Class

DOMExample first creates a DOM document by parsing an XML document. The file it parses is one that you specify on the command line.

static Document document;
...
    DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
    factory.setNamespaceAware(true);
    try {
        DocumentBuilder builder = factory.newDocumentBuilder();
        document = builder.parse( new File(args[0]) );
        ...

Next, the example creates a SOAP message in the usual way. Then it adds the document to the message body:

        SOAPBodyElement docElement = body.addDocument(document);

This example does not change the content of the message. Instead, it displays the message content and then uses a recursive method, getContents, to traverse the element tree using SAAJ APIs and display the message contents in a readable form.

public void getContents(Iterator iterator, String indent) {

    while (iterator.hasNext()) {
        Node node = (Node) iterator.next();
        SOAPElement element = null;
        Text text = null;
        if (node instanceof SOAPElement) {
            element = (SOAPElement)node;
            QName name = element.getElementQName();
            System.out.println(indent + "Name is " + name.toString());
            Iterator attrs = element.getAllAttributesAsQNames();
            while (attrs.hasNext()){
                QName attrName = (QName)attrs.next();
                System.out.println(indent + " Attribute name is " +
                     attrName.toString());
                System.out.println(indent + " Attribute value is " +
                     element.getAttributeValue(attrName));
            }
            Iterator iter2 = element.getChildElements();
            getContents(iter2, indent + " ");
        } else {
            text = (Text) node;
            String content = text.getValue();
            System.out.println(indent + "Content is: " + content);
            }
        }
    }

Examining the `DOMSrcExample` Class

DOMSrcExample differs from DOMExample in only a few ways. First, after it parses the document, DOMSrcExample uses the document to create a DOMSource object. This code is the same as that of DOMExample except for the last line:

    static DOMSource domSource;
    ...
    try {
        DocumentBuilder builder = factory.newDocumentBuilder();
        Document document = builder.parse(new File(args[0]));
        domSource = new DOMSource(document);
        ...

Then, after DOMSrcExample creates the message, it does not get the header and body and add the document to the body, as DOMExample does. Instead, DOMSrcExample gets the SOAP part and sets the DOMSource object as its content:

// Create a message
SOAPMessage message = messageFactory.createMessage();

// Get the SOAP part and set its content to domSource
SOAPPart soapPart = message.getSOAPPart();
soapPart.setContent(domSource);

The example then uses the getContents method to obtain the contents of both the header (if it exists) and the body of the message.

The most important difference between these two examples is the kind of document you can use to create the message. Because DOMExample adds the document to the body of the SOAP message, you can use any valid XML file to create the document. But because DOMSrcExample makes the document the entire content of the message, the document must already be in the form of a valid SOAP message, and not just any XML document.

Building and Running the DOM and DOMSource Examples

When you run DOMExample and DOMSrcExample, you can specify one of two sample XML files in the directory tut-install/javaeetutorial5/examples/saaj/dom/:

slide.xml, a file that consists only of a message body
domsrc.xml, an example that has a SOAP header (the contents of the HeaderExample SOAP 1.1 output) and the same message body as slide.xml

You can use either of these files when you run DOMExample. You can use domsrc.xml to run DOMSrcExample.

To build the programs using NetBeans IDE, follow these steps:

In NetBeans IDE, choose Open Project from the File menu.
In the Open Project dialog, navigate to tut-install/javaeetutorial5/examples/saaj/.
Select the dom folder.
Select the Open as Main Project check box.
Click Open Project.

A Reference Problems dialog appears. Click Close.
Right-click the dom project and choose Resolve Reference Problems.
In the Resolve Reference Problems dialog, select the first of the missing JAR files and click Resolve.

The missing files are activation.jar, javaee.jar, and appserv-ws.jar.
Navigate to the as-install/lib/ directory.
Select the missing JAR file (activation.jar, for example) and click Open.

In the Resolve Reference Problems dialog, all the files have green check marks to the left of their names.
Click Close.
Right-click the project and choose Build.

To run DOMExample using NetBeans IDE, follow these steps:

Right-click the dom project and choose Properties.
Select Run from the Categories tree.
Click Browse next to the Main Class field.
In the Browse Main Classes dialog, select DomExample.
Click Select Main Class.
In the Arguments field, type the following:
slide.xml
Click OK.
Right-click the project and choose Run.

To run DOMSrcExample using NetBeans IDE, follow these steps:

Right-click the dom project and choose Properties.
Select Run from the Categories tree.
Click Browse next to the Main Class field.
In the Browse Main Classes dialog, select DomSrcExample.
Click Select Main Class.
In the Arguments field, type the following:
domsrc.xml
Click OK.
Right-click the project and choose Run.

To run the examples using Ant, go to the directory tut-install/javaeetutorial5/examples/saaj/dom/.

To run DOMExample using Ant, use the following command:

ant run-dom -Dxml-file=slide.xml

To run DOMSrcExample using Ant, use the following command:

ant run-domsrc -Dxml-file=domsrc.xml

When you run DOMExample using the file slide.xml, you will see output that begins like the following:

     Running DOMExample.
     Name is slideshow
      Attribute name is author
      Attribute value is Yours Truly
      Attribute name is date
      Attribute value is Date of publication
      Attribute name is title
      Attribute value is Sample Slide Show
      Content is: 
...

When you run DOMSrcExample using the file domsrc.xml, you will see output that begins like the following:

     Running DOMSrcExample.
     Header contents:
     Content is: 

     Name is {http://gizmos.com/NSURI}orderDesk
      Attribute name is SOAP-ENV:actor
      Attribute value is http://gizmos.com/orders
     Content is: 
    ...

If you run DOMSrcExample with the file slide.xml, you will see runtime errors.